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The email addresses for Dirac Delta Consultants, the authors of the Science and Engineering Encyclopaedia.
Embankment Dam
A dam composed of a mound of earth and rock; the simplest type of gravity dam.
Embossing
Raising or indenting a design in relief on a sheet or strip of metal by passing between two patterned rolls.
Embrasure
A splayed opening in a wall that enframes a doorway or a window.
Embrittlement
Reduction in ductility due to physical or chemical changes.
Embryo
A young animal growing inside it′s mother or growing inside an egg.
EMC
Abbreviation of Electromagnetic Compatibility.
Emergency Power
Temporary source of limited electrical power used upon the loss of the normal power source.
Emery
A natural abrasive used for grinding or polishing.
Emery Cloth
Fabric backed abrasive paper.
EMF
Abbreviation of Electro Motive Force.
EMI
Abbreviation of Electromagnetic Interference.
Emission Nebula
A type of nebula that shines by emitting light when electrons recombine with protons to form hydrogen atoms.
Emission Spectrum
The collection of discrete wavelengths emitted by atoms that have been excited by heating or by electric currents.
Emissions
The gases and airborne particles produced during combustion.
Emissivity
The ratio of the radiant energy emitted by a any source to that emitted by a blackbody at the same temperature.
Emittance
The rate at which emission occurs.
Emitter
One terminal of a transistor. Compares generally to the cathode of a tube.
Emitter Coupled Logic
Where transistors are held in the turned-on state to increase the speed of the gate.
Emitter Follower
A transistor circuit comparable to the cathode-follower tube circuit. (Also called grounded collector.)
Emollient
A substance added to a formulation that gives it softening ability.
EMP
Abbreviation of Electromagnetic Pulse.
Emphasis
Filtering applied to an audio signal before storage or transmission to improve the signal-to-noise ratio at high frequencies.
Empirical Law
A law strictly based on experiment, which may lack theoretical foundation.
Empirical Temperature
A property that is the same for any two systems that are in thermodynamic equilibrium with each other.
Empty Set
The set with no elements in it.
Emulsion
A colloid formed from tiny liquid droplets suspended in another, immiscible liquid. E.g. Milk.